Immune support
The Surprising Connection Between Your Gut and Your Immune System
Most of your immune tissue sits along your digestive tract
Most people reach for vitamin C when they feel run down. Here's why researchers keep looking at the gut instead, and what that means for everyday immune support.
Respiratory & Immune at a glance
- 65BCFU from 65 strains per serving
- 81.5%Lactobacillus (53B), with 12B Bifidobacterium
- 4biotics: prebiotics, probiotics, postbiotics and parabiotics
The short version
- About 70% of your immune system sits in the lining of your gut, in tissue called GALT.1
- Your gut and lungs talk to each other through the gut-lung axis, so what happens in your gut can shape immune activity in your airways.2,3
- Specific strains, including Bl-04, DR7 and CRL-1505, have been studied for respiratory and immune markers.4,5,6
- Sleep, stress, fermented foods and a targeted probiotic all feed the same system. Consistency matters more than timing.*
When winter rolls around, we tend to focus on the respiratory tract: the sniffles, coughs and congestion. But the foundation of your immune system sits much lower, in your digestive system.
This gut-immune connection is more than interesting biology. It changes how you think about staying well year-round, and it explains why researchers study specific probiotic strains for respiratory and immune health. Diet feeds the same conversation: the beta-glucan fibers in functional mushrooms like reishi and turkey tail are another substrate your gut bacteria ferment, and they're an active area of gut-immune research.
Where your immune system really lives
Your gut microbiome communicates directly with immune cells, helping train them to tell friend from foe. That happens in gut-associated lymphoid tissue, or GALT, the largest immune organ in your body. The rest of the immune system (lymph nodes, spleen and bone marrow) makes up the remainder.1
About 70%
Gut-associated lymphoid tissue
The immune tissue that lines your digestive tract, where immune cells meet what you eat and the bacteria that live there.1
The rest
Lymph nodes, spleen, bone marrow
The parts of the immune system most of us picture first. They rely on signals that start in the gut.
How gut bacteria support your respiratory health
The relationship between your gut and your lungs is called the gut-lung axis: gut microbes influence immune responses in the airways.2 When your gut microbiome is balanced, it produces compounds that travel through your bloodstream and influence immune activity throughout your body, including your respiratory tract.
Beneficial bacteria in your gut support immune function in several ways: they compete with unwanted microbes for space and food, produce their own protective compounds, support the gut barrier that keeps unwanted substances out of your bloodstream, and communicate directly with immune cells to keep them alert but balanced.
Key insight
Research on the gut-lung axis suggests that the makeup of your gut microbiome shapes how your immune system responds in your airways. A diverse, balanced microbiome is part of a healthy immune foundation.3
Immune readiness assessment
Five quick questions about your immune foundation
Based on the habits discussed in this article. Not a diagnosis, and not a substitute for your provider's advice.
How often do seasonal bugs knock you off your routine?
How would you describe your digestion?
How often do you eat fermented foods?
How much sleep do you usually get?
How would you rate your stress?
Your starting point
Start with digestive comfort
Your gut is where most of your immune tissue lives, so frequent digestive discomfort is the first thing to look at. If it's ongoing, talk with your provider to rule out anything that needs care.
Day to day, a targeted probiotic supports a balanced microbiome and healthy immune function.*
Your starting point
Rest and stress come first
Short sleep and high stress are both stretching your immune foundation at once. Protecting your sleep and building in recovery will do more than anything you add.
DR7, one of the strains in Respiratory & Immune, was studied for both stress and immune markers.5 It supports healthy immune function alongside those habits.*
Your starting point
Protect your sleep
Of the habits we asked about, sleep is the biggest gap. Seven to nine hours is where your immune system does its maintenance work, so it's the first lever to pull.
A daily targeted probiotic supports healthy immune function while you rebuild the routine.*
Your starting point
Mind the stress side
Stress hormones can dampen immune activity and affect the gut barrier. Your sleep looks good, so managing stress is the lever with the most room.
DR7 was studied for both stress and immune markers.5 Respiratory & Immune includes it to support both sides of that connection.*
Your starting point
Feed your microbiome
Sleep and stress look good. The gap is food for your gut bacteria. Add a fermented food a few times a week, plus fiber-rich plants and mushrooms, to give your microbiome more variety.
A targeted probiotic adds studied strains while you build the habit.*
Your starting point
Solid habits, worth a check-in
Your sleep, stress, diet and digestion are all in good shape, yet you're getting run down often. That's worth a conversation with your provider to see what else is going on.
Alongside their advice, a targeted probiotic supports healthy immune function.*
Your starting point
Strong immune foundation
Your lifestyle supports healthy immune function on every count we asked about. Keep it steady, especially through busy or stressful stretches.
A targeted probiotic can help you maintain that foundation year-round.*
Your starting point
Good foundation, a little room
Your habits are in good shape and your digestion has only the occasional off day. Consistent fiber, fermented foods and steady sleep help keep your gut, and the immune tissue that lines it, in balance.
A daily targeted probiotic supports digestive and immune health together.*
The science of immune-targeted probiotics
Not all probiotics are studied for the same things. Certain strains have been researched specifically for immune function and respiratory health, so the key is matching the strain to the purpose.
Clinically studied strains for immune support
These three strains are in Respiratory & Immune. The studies below tested single strains, not our blend, so read them as research on the strains.
Bifidobacterium animalis subsp. lactis. Studied in healthy, physically active adults for respiratory and digestive symptoms, and for how it modulates immune responses in the airways.4
Lactobacillus plantarum. Researched for both stress response and immune markers in adults. Stress can weigh on immunity, which makes this dual focus useful.5
Lactobacillus rhamnosus. Studied in animal research for how an orally taken strain influences the immune response in the respiratory tract, a direct look at the gut-lung axis.6
Inside the formula
Why Lactobacillus-dominant formulas matter for immunity
Respiratory & Immune
Why this ratio?
Lactobacillus strains, including DR7 and CRL-1505, have been studied for how they interact with immune responses and for respiratory health.5,6 A Lacto-forward blend gives targeted immune support while keeping overall microbiome balance.*
How it differs from a general probiotic
General formulas often focus on digestive comfort. This one adds studied immune strains and a higher Lactobacillus share on top of daily gut support.*
Beyond probiotics: the 4-Biotic approach
Single-strain probiotics can be helpful, but immune support benefits from a more complete approach. Respiratory & Immune combines four types of microbiome-supporting compounds.
1
Prebiotics
Specialized fibers that feed beneficial bacteria, helping immune-supporting strains thrive in your gut.*
2
Probiotics
65 billion CFU from 65 strains, including strains studied for immune support.*
3
Postbiotics
Beneficial compounds produced by probiotic metabolism that support immune cell function.*
4
Parabiotics
Heat-treated beneficial bacteria that interact with immune cells without colonizing the gut.*
When to consider immune-targeted probiotics
Probiotics can be useful year-round, but some stretches call for extra immune support:*
-
Seasonal transitions
As the weather changes, your body adjusts. Fall and winter bring more time indoors and more exposure to seasonal bugs.
-
High-stress periods
Stress hormones can dampen immune activity. During demanding stretches at work or big life changes, gut-immune support is especially useful.*
-
Travel
New environments, disrupted sleep and stress all weigh on your defenses. Supporting your gut before and during a trip may help.*
-
After antibiotics
Antibiotics can disrupt your gut bacteria. Replenishing beneficial strains helps support that foundation.* See our guide to probiotics with antibiotics for timing.
Targeted gut-immune support
Respiratory & Immune | Intense Care
Clinically studied strains for gut-immune support. 65 billion CFU from 65 strains, including Bl-04, DR7 and CRL-1505, with organic prebiotic fiber, in a Lactobacillus-forward blend made to support healthy immune function.*
- 65 billion CFU
- 65 diverse strains
- Bl-04, DR7, CRL-1505
- Organic prebiotic fiber
Common questions about gut health and immunity
Some gut health benefits can show up within weeks, but immune support usually becomes more apparent over 2-3 months of consistent use. That gives beneficial bacteria time to settle in and begin influencing immune cell activity. If you want extra support heading into winter, start a few weeks before the season gets going.*
Yes, probiotics pair well with other immune-supporting nutrients. Vitamin C, zinc and vitamin D work through different mechanisms than probiotics, so combining them gives layered support. Probiotics address the gut-immune connection, while vitamins and minerals support immune cell function directly.*
Respiratory & Immune features specific strains studied for immune function (Bl-04, DR7 and CRL-1505) and a higher Lactobacillus ratio (81.5%) chosen for immune support. General probiotics may focus more on digestive comfort or overall gut health, without targeted strains for respiratory and immune support.*
Consistent, year-round use gives the most complete support, because it keeps your gut bacteria in balance all the time. If you prefer seasonal use, start at least 4-6 weeks before winter so the strains have time to settle in. Many people notice the most benefit from steady daily use.*
Chronic stress raises cortisol, which can dampen immune cell activity and affect gut barrier function. Certain strains, like DR7 in this formula, have been studied for their effect on the stress response alongside immune markers, so they speak to both sides of that connection.5*
Building long-term immune resilience
Immune strength isn't built overnight. It comes from consistently supporting your body's natural defenses. Nurturing the gut-immune connection with targeted probiotic strains builds a foundation that serves you all year, not only in winter.*
The research points the same way: a balanced, diverse gut microbiome is a core part of healthy immune function.1,3 Combined with enough sleep, stress management and a nutrient-rich diet, probiotic support helps your body stay resilient through whatever the season brings.*
References
- Mörbe UM, et al. Human gut-associated lymphoid tissues (GALT); diversity, structure, and function. Mucosal Immunol. 2021;14(4):793-802. PubMed
- Enaud R, et al. The Gut-Lung Axis in Health and Respiratory Diseases: A Place for Inter-Organ and Inter-Kingdom Crosstalks. Front Cell Infect Microbiol. 2020;10:9. PubMed
- Dumas A, et al. The role of the lung microbiota and the gut-lung axis in respiratory infectious diseases. Cell Microbiol. 2018;20(12):e12966. PubMed
- West NP, et al. Probiotic supplementation for respiratory and gastrointestinal illness symptoms in healthy physically active individuals. Clin Nutr. 2014;33(4):581-7. PubMed
- Chong HX, et al. Lactobacillus plantarum DR7 improved upper respiratory tract infections via enhancing immune and inflammatory parameters: A randomized, double-blind, placebo-controlled study. J Dairy Sci. 2019;102(6):4783-4797. PubMed
- Villena J, et al. Orally administered Lactobacillus rhamnosus modulates the respiratory immune response triggered by the viral pathogen-associated molecular pattern poly(I:C). BMC Immunol. 2012;13:53. PubMed